1. Field of the Invention
The present invention relates to magnetic resonance imaging apparatuses, and more particularly to bed devices to feed subjects into imaging spaces and table tops of the bed devices.
2. Description of the Related Art
A table top to feed a subject into an imaging space for example of a MRI apparatus is required to be nonmagnetic and nonconductive to prevent observing a magnetic resonance phenomenon in the subject. Therefore, the table top is conventionally composed of a wood material. Recently, to be craft friendly or for weight saving, it has become common for the table top to be composed of glass fiber reinforced plastic (G-FRP) (see Jpn. Pat. App. KOKAI Publication No. 2008-006200).
However, recently it is necessary for an MRI apparatus to scan a wide range with one search for a screening scan etc. Therefore, a range of movement for the bed device has widened. A wider range of the bed device improves a maximum overhang length from the bed device to the table top. Meanwhile, a magnetic gantry that generates static magnetic control that tends to shorten an axis and consequently the length of a projecting part of the table top in the direction of backward of the magnetic gantry (opposite side of the bed device) has had to be lengthened. Therefore, the table top is being required to support a greater load.
From the above facts, sometimes wood and G-FRP do not provide all the properties currently being required from the bed device. In addition, although G-FRP gives a certain level of strength of the bed device by heightening to a filling fraction of a glass fiber in the G-FRP, the more the filling fraction of the glass fiber in G-FRP is increased, the greater a strain in molding the G-FRP and the heavier the G-FRP.